This invention relates to compacted particle aluminum sheets of the type described in U.S. Pat. Nos. 3,076,706 and 3,246,982; and, more particularly, to the production of heavy guage compacted particle aluminum sheets and compacted particle aluminum sheets having improved properties.
In the past it has been difficult to make compacted particle aluminum sheets having a thickness of more than about 0.070 inch. The instant invention, however, permits the production of much thicker compacted particle aluminum sheets which permit their use in high-strength-requirement products such as aluminum sheet bumpers for automobiles. Moreover, an advantage of such sheets is that they have a desirable structure resulting from a fine dendritic cell size in rapidly solidified particles which is not obtainable from sheets produced from ingot material. Additionally, the instant invention can be used to provide compacted particle aluminum sheets having an improved transverse ductility.
The invention also relates to the production of relatively inexpensive aluminum sheets from recycled aluminum scrap. In this respect, one of the problems in using recycled aluminum has been the need to use expensive methods for reducing impurities in the recycled metal because conventionally produced aluminum alloys are usually unsatisfactory unless recycling impurities are substantially reduced. The instant invention, however, permits the use of recycled aluminum in a manner so that expensive impurity-removal steps need not be taken while the resulting product nevertheless has the qualities that are desired from higher purity alloys.